Cell Division - Meiosis

Question 1

Very simply define Meiosis compared with mitosis

Answer 1

Mitosis: makes identical cells

Meiosis: Makes cells with half DNA from one gamete, half from another

Question 2

How many chromosomes do gametes have compared to normal cells?

Answer 2

Half

Question 3

When are gametes used?

Answer 3

In sexual reproduction

Question 4

What happens during sexual reproduction?

Answer 4

2 gametes (sex cells) combine to form a new individual

Question 5

How many copies of each chromosome do gametes have?

Answer 5

Only 1

Question 6

Why do gametes only have 1 copy of each chromosome?

Answer 6

So that you can combine one sex cell from the ‘mother’ and one from the ‘father’ and still end up with the right number of chromosomes in body cells

Question 7

How does sexual reproduction produce variation?

Answer 7

The new individual will have a mixture of two sets of chromosomes, so it will inherit features from both parents

Question 8

Meiosis produces cell which have ____ the normal number of ____

Answer 8

Meiosis produces cell which have half the normal number of chromosomes

Question 9

Describe the steps for the 1st division in meiosis

Answer 9

1. The strands of DNA coil up in the nucleus to become visible
2. The DNA duplicates itself
3. Pairs line up in the centre of the cell
4. The pairs are pulled apart, so each new cell only has one copy of each chromosome
5. Some chromosomes from both the mother and the father go into each cell

Question 10

Describe the 2nd division in meiosis (2)

Answer 10

1. The chromosomes line up in the centre of the cell (again)
2. The arms of the chromosomes are pulled apart

Question 11

What happens after 2 gametesjoin at fertislisation?

Answer 11

The cell grows by repeatedly growing by mitsosis

Question 12

In meiosis, you get ____ gametes each with only 1 set of chromosomes

Answer 12

In meiosis, you get 4 gametes each with only 1 set of chromosomes

Question 13

Draw a diagram of meiosis

Answer 13